1. Technical Field
This document discloses a hydraulic fluid circuit for actuating a clutch pack of a hydraulic clutch assembly for use in a motor vehicle driveline.
2. Description of the Related Art
Rotary powered transmission systems, such as transfer cases, rear differentials and front differentials may employ hydraulically actuated clutches. These clutches are controlled with a hydraulic fluid circuit. Conventional hydraulic fluid circuits for clutch actuation are typically closed systems, and include a reservoir within the driveline assembly to accommodate any loss of fluid due to leakage or changes in the system due to thermal effects. Because some of the hydraulic fluid from the hydraulic fluid circuit is typically lost over time, the reservoir may need to be accessed externally for replenishing the circuit with hydraulic fluid. However, for many vehicles, access to the reservoir is difficult because of the tight packaging of driveline components surrounding the reservoir and the corresponding tortuous pathway to the reservoir. Therefore, replenishing the reservoir as a part of regular maintenance procedures is time consuming and costly.
Thus, there is a need for a hydraulic clutch assembly that can automatically or actively refill or replenish its hydraulic fluid circuit without resorting to a costly maintenance procedure.